• Journal of Communications and Networks
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• v.5 no.3
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• pp.187-196
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• 2003

We consider the use of error control coding in direct sequence-code-division multiple access (OS-COMA) systems that employ multiuser detection (MUO) and space diversity. The relative performance gain between Reed-Solomon (RS) code and convolutional code (CC) is well known in [1] for the single user, additive white Gaussian noise (AWGN) channel. In this case, RS codes outperform CC's at high signal-to-noise ratios. We find that this is not the case for the multiuser interference channel mentioned above. For useful error rates, we find that soft-decision CC's to be uniformly better than RS codes when used with DS-COMA modulation in multiuser space-time channels. In our development, we use the Gaussian approximation on the interference to determine performance error bounds for systems with low number of users. Then, we check their accuracy in error rate estimation via system's simulation. These performance bounds will in turn allow us to consider a large number of users where we can estimate the gain in user-capacity due to channel coding. Lastly, the use of turbo codes is considered where it is shown that they offer a coding gain of 2.5 dB relative to soft-decision CC.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.9B
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• pp.1616-1623
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• 1999

This paper describes error resilient coding scheme is added in WLL system and its application for robust low-bit rate still image transmission over power controlled W-CDA system Rayleigh fading channels. The baseline JPEG compressing methods are uses in image coding over wireless channel. The channel uses Reed-Solomon(RS) outer codes concatenated with convolutional inner codes, and truncated type I hybrid ARQ protocol based on the selective repeat strategy and the RS error detection capability. Simulation results are proved for the statistics of the frame-error bursts of the proposed system in comparison with conventional WLL system. it gains the 2 dB of the Eb/No in same BER.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.8C
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• pp.763-770
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• 2006

In this paper, a variable Reed-Solomon(RS) decoder with erasure decoding functionality is designed based on the modified Euclid's algorithm(MEA). The variability of the decoder is implemented through shortening and puncturing based on the RS(124, 108, 8) code, other than the primitive RS(255, 239, 8) code. This leads to shortening the decoding latency. The decoder performs 4-step pipelined operation, where each step is designed to be clocked by an independent clock. Thus by using a faster clock for the MEA block, the complexity and the decoding latency can be reduced. It can support both continuous- and burst-mode decoding. It has been designed in VHDL and synthesized in an FPGA chip, consuming 3,717 logic cells and 2,048-bit memories. The maximum decoding throughput is 33 MByte/sec.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.3 s.357
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• pp.61-67
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• 2007

In Reed Solomon decoder, when there are more than 4 error symbols, we usually use Chien search machine to find those error positions. In this case, classical method requires complex and relatively slow digital circuitry to implement it. In this paper we propose New fast and cost effective Chien search machine design method using Galois Subfield transformation. Example is given to show the method is working well. This new design can be applied to the case where there are more than 5 symbol errors in the Reed-Solomon code word.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.2
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• pp.22-28
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• 2007

High PAPR (peak-to-average power ratio) is a major drawback of OFDM (orthogonal frequency division multiplexing) signals. In this paper, a modified SLM (selective mapping) technique that uses erasure decoding of RS (Reed-Solomon) codes is presented. At the transmitter a set of phase sequences are multiplied such that some portions of check symbols in RS-coded OFDM data blocks are phase-rotated. At the receiver, RS decoding is performed with the phase-rotated check symbols being treated as erasures. Hence, there is no need to send side information about the phase sequence selected to transmit for the lowest PAPR. In addition, the estimation process for the selected phase sequence is no longer needed at the receiver, leading to improvement in terms of complexity and performance. To evaluate the performance of this technique, the CCDF (complementary cumulative distribution function) of PAPR, the BER (bit error rate) and the decoding failure probability are compared with those of the previous SLM techniques.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.10
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• pp.2247-2255
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• 2015

In very shallow water acoustic communication channel, underwater acoustic (UWA) communication signal is observed as frequency selective fading signal due to time-varying multipath. This induces a time and frequency dependent inter-symbol-interference (ISI) and degrades the UWA system performance. There is no study about how the performances of the error correction codes are related to a multipath fading statistics in very shallow water. In this study, the characteristics of very shallow water multipath fading channel is analyzed and the performances of two different forward error correction (FEC) codes are compared. The convolution code (CC) and Reed-Solomon (RS) code are adopted. Sea experimental results show that RS code is better choice than CC in frequency selective channel with fading.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.45 no.4
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• pp.35-41
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• 2008

When memory devices are exposed to a space environment. they suffer various effects such as SEU(Single Event Upset). For these reasons, memory systems for space applications are generally equipped with error detection and correction(EDAC) logics against SEUs. In this paper, the error detection and correction strategy in the Mass Memory Unit(MMU) of the STSAT-3 is discussed. The probability equation of un-recoverable SEUs in the mass memory system is derived when the whole memory is encoded and decoded by the RS(10,8) Reed-Solomon code. Also the probability value is analyzed for various occurrence rates of SEUs which the STSAT-3 possibly suffers. The analyzed results can be used to determine the period of scrubbing the whole memory, which is one of the important parameters in the design of the MMU.

• Journal of Korea Society of Industrial Information Systems
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• v.22 no.3
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• pp.19-26
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• 2017

In this paper, a Linear Error Correction Code, Which is Applicable to Next Generation Wireless Communication System Technology, is Constructed Based on Performance Comparison and Transmission Based on the Premise of High Performance Mobile Rate Enhancement System. This is Because Data Rates are Becoming an Important Issue in Reed-Solomon Codes and Linear Error Code (LDPC) Used in the Physical Layer of Digital Communication and Broadcasting Technologies. Therefore, this paper Simulates the Performance of Reed - Solomon Code and LDPC Applied to Mobile Broadcasting DVB (Digital Video Broadcasting) System and Mobile Broadcasting in Digital Communication and Broadcasting, At this time, Technical Aspects of the Transmission Efficiency and Performance of the LDPC Replacing the Existing Reed-Solomon Code have been Verified from the Viewpoint of Efficiency.

• Journal of the Korean Institute of Telematics and Electronics T
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• v.35T no.1
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• pp.59-66
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• 1998

In this paper, the high-speed decoder for RS(Reed-Solomon) code, one of the most popular error correcting code, is implemented using VHDL. This RS decoder is designed in transform domain instead of most time domain. Because of the simplicity in structure, transform decoder can be easily realized VLSI chip. Additionally the pipeline architecture, which is similar to a systolic array is applied for all design. Therefore, This transform RS decoder is suitable for high-rate data transfer. After synthesis with FPGA technology, the decoding rate is more 43 Mbytes/s and the area is 1853 LCs(Logic Cells). To compare with other product with pipeline architecture, this result is admirable. Error correcting ability and pipeline performance is certified by computer simulation.

• Information and Communications Magazine
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• v.12 no.6
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• pp.88-100
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• 1995

본 고에서는 디지털 위성방송 시스템의 구성요소중 channel부의 구조 및 기능분석을 국내 디지털 DBS를 기준으로 설명하였다. channel부는 channel coding과 modulation 기능을 수행한다. Channel coding은 Reed Solomon code, interleaving, convolutional code를 연집하여 사용하고, modulation은 QPSK와 raised cosine pulse shaping을 한다. 수신기의 channel부는 antenna, LNB, tuner, QPSK 복조기, Viterbi, deinterleaver, RS decoder로 구성되어있다.